Railway signaling system



July 3, 1945., I o. s. FI ELD RAILWAY SIGNALING SYSTEM ,Origihal- Filed Fb. '14, 1941 lBY Lm uoL E3 v w a u a 3 fic oow m w w A QW Q n i v m N W A w n tions I, 2, 3 and 4;

Patented July 3, 1945 RAILWAY SIGNALINGSYSTEM Oscar ,s. Field, Rochester, 1N. y, assignor to GeneralRailway Signal Company, Rochester Originalapplication' February 14, 1941', Serial No.

378,966; Divided and this application Novemher 4, 1942, Serial No. 464,520 I .2 claims- (Cl.24634 v This invention relates in general to railway signaling systems and has more particular reference to wayside signaling systems employing type SC search light type signals.

The type SQv search light signal is constructed and operates as disclosed in the Field application, Ser. No. 361,060, filed October 14, 1940.

This application is a division of -my pending application, Ser. No. 378,966, filed February 14, 1941, for Railway signaling system, now Patent No. 2,313,468 dated March 9, 1943. 1

This type SC signal'has a single spectacle carrying a plurality of coloredglasses through one of which at a time light from a single'light source is directed to give a signal indication. The spectacle is moved to various indicating positions by two separate mechanisms or relays which" also operate various contacts'and because of this con- 7 struction,'many of the usually employed relays such as line relays, repeating relays, etc,,t generally used in signaling systems, can be dispensed with since the operating mechanisms of the signals themselves can serve the added-function of these otherwise necessary relaysi ing the single figure is a diagrammatic representation of one form of the invention.

. current so passed to energize a code following relay CR. Relay CR picks up andstays up .wh11e Referring 'now to the drawing, there is here shown a signaling system of the coded trackway type wherein code is-placed on the track rails and no line wires are employed. A stretcho'f's'ingle track constituted bytrack' rails 6 is divided into aplurality of isolated track sections by usual insulating joints 1 whereby to form the track'sec- At the entrance end of each track section, traffic being eastward'as indicated by arrow 8, is a wayside signal designated by S, with a suitable suflix corresponding to the section with which it is associated. Section 4, as represented, is 00- cupied by a vehicle 9.

Since the apparatus employed at each signalv location is the same throughout the system only the apparatus at one location, that of signal S2, has been shown in any detail.

Connected across the entrance end of each section, as section 2, is a filter and rectifier ID for passing current freely only if of a given frequency such as 100 cycles whereby not to pass the usual commercial frequencies and to rectify the code current is flowingand releases, and stays released, between the separate code current impulses whereby to pick up'i-and release for each code impulse to therebyoperate its contact: fina red-yellowrelay ltYlR, and a yeuqw-g njejlay YGRl for operating aspectacle SP carrying colored roundels G, Y and R colored respectively green, yellow and red with reference to' a light source 13 whereby to give varioussignalaspects. Each operating relay of thesignal hasfanfencrgizing circuit connected to a portion-of the secondary winding ofthie transformer through fullwave rectifiers as HI and '15.. The circuit*between the transformer-secondary and therectifier of the yellowfgreen' relay is tuned to-jfsjubstantial resonance at a frequency of 180' per r'n'inute whereby to cause'the yellow-green relay to res'pondonly to the 180 code. A lower rate code, namely, is employed and sincelthe circuit for the red-yellowv relay is not tuned,,this; relay responds to each of the codes.-

' As disclosed in the applicationabove, referred to, thespectacleis biased to display themred indication when bothoperating relays-aredeenergized; It displays the yellowindication when the red-yellow-relay only is energized and the green indication when'both operating relaysare energized. A

Across the exit end of each sectiong'ias," for example, section I, is connected the primary winding of a track transformerTIR- ins'eries with an adjustable reactance Hi. The primary winding of this transformer is connected by wire IT to contact finger l8 of the red-yellow relay to the front point of which finger is connected rent is connected across the r s, a d e sense. It is to be understood that various modilays CR are connected directly across the rails. fications, adaptations, and alterations may be ap- Considering the operation of the system as deplied to meet the requirements of practice withscribed above, it is clear that with section 4 out in any manner departing from the spirit or cupied by a vehicle the code is shunted by the scope of this invention, except as clearly limited wheels and axle shunts from the code following by the appended claims.

relay forhithatiblocklwherebyits signal S4-is'1com- Having; described my-zinvention, I now claim: pletely d'eenergized and" hence displays a red in- 1. In a coded railwaysignaling 'system, in comdication. bination, a section of railway track, a light sig- With signal S4 having its red-yellow relay-de nal at the entrance end of said section, said sigenergized, code at the rate of .-75.- impulsesr;--per .nal being of a typ which has a member biased to minute is applied to the exit end of section 3 afirst position in whioh'it conditions the signal to whereby the red-yellow relayof-signa1S3 isenerprovide onedndication, electro-responsive means gized, but its yellow-greenrelay'is-notenergized, associatedwith'said member and eilective when and hence, this signal displays a yellow indical5 energ ed o us nt of d member, a tion. coden-following relay, means governed by traific With signal S3 having its-"redeyellow -relay nwconditi'ons inzsaid section for at times supplying to ergized, code at the rate of 180 impulses per minl verey Of O Code frequency and at ute is placed on section- 2 whereby .toaenergiz'e eri e s pp ying t id r l y n r y f both of the control relays of signal S2 and cause another code frequency, a decoding transformer,

:' :itsto displaysa*greendndicatiomeall; asrillustrated. =z. .means respons e to operationwfvsaid relay by riInelikez-manner;section .|;':andeal1 sections to --:energy:of:e then-code.freque y for varyi tithe rear thereofwprovidingcthere: isno'othermccv. ergizations':of;:the: primary winding of said-trans- -rcupancwdisblays.agreen:iridication. former, meansaefiectivesrwhena saidwrelay is re- ;z ltmambeseeriifromzthefabovezthatimthis sys- =spondingv to energyofath -ifirsttcode. :firequency rtem'semployingzther rtypefSCl= signal; ithefcDde se- --wtosupp y fr he {decoding -r nsf rmer tos i dectionl :ior'rthe: block to rthe rear =ofzazgiven block electro responsiveim'eans energy fiectiveto cause --sis controlled-ibyuthered yellowirelay which-irelay movement: ofi said'ememberxto a: position in which s a-lso'nperates 'the.-1 speetacle. r 'lhi relay,--.together s it conditions-the signal to lprovidela 'secondindicwith a'the yellow-green -relamuis made :sufficiently 30.1cation;andcmeansnefiiective whenusaid' relay is slow: tor-release so :that a 'momentaryechange' :of responding to-en'ergy of'lthe other: code frequency mode:doesnnotr:chang sthewsignal:- aspect, rand ntoi supplyifromixthe decoding 'transformer to said vhenoewseveral cycles: of m'eWt-codemustrhaye oc- ,electro responsiveimeanssenergyrefiective:to cause eurredhefore-the signal :responds. This cares for sxzmovement of said; membernto 1 pnsition:jn:which dead sections, crossovers, and the like. =:itncomiitionsrthesignalto provide a thirdrindica- Itiisv aurthermore apparent that with-this type an of signal, ,in =changi g= ofathe oodenfrom the- 75 2;;1In.acodedzrailway signaling system; in com- =rate to. the 1-80 rate to =.change f-rom,-a yellow inbinatinm-q 91-:sECtlOnE'OfiZI'allWayLiIECk;.a, hghbt sjg ,-.Hdication:;itosa green indication, the redeyellow nnaI-atthe-entrance end ofssaidsectiom-said signal melfly semomentaiilyadeen gizedJout.due. to.. its being; of aztypemavingl amembersbiasedtto azfirst cslowi release.-.characteristics its does mot release pposition in whichiit: conditions .the "signal toup sbut re ainauliso Q-QrcVentaflaSh-ofithe red --ivide:a; firstrindication, a first control windings-f- "indication while the signal, is chan ing from lcfeeti-ve whenv energized :tormove said :memben to a .IoWJtQ-green. second positiomimwhichrit:conditionsthasign'al .'The,typerSA.searchlightsignal many of which ;to ;'prov.ide a seconduindication; a-secondi control .areineuse, isi'of thep l r tyneandhasaspectacle wwinding: effective rwhens:energizedpt :move=-ssaid Lhiasedto almiddle position toudisp fiy the red id member: to: a ithird position in which it; aconclication and is moved to either side of the middle xtions the. signal to provide axthirdxindication a positionrtd'display the yellow andgreen 'indicaaeodenfollowing- -re1ay,-;means governed byltralfic 'tions upon change in LthBDOIaIitY' of energiza- Q conditions in said-sectioniorat time supplying tion. 4"Thus,"it is clearthat such a signal could-riot tosaid relaycodedtenergy ofafirst charactenand "fip l C dWT aYSy te of'the'type at other timessupplying to said relay codedaendlscl'osedabove. eergyl rof a; second. character; a decoding .l-trans- Withth-typeSC.signali'however, a coded 'sysformer; means responsiveitdoperationof said retem having separatedecoding relays'cor-respond- '55.,alay byncoded; energyeofeither.charac-ter-forvary- "'ing' to the-'operating'relays of the-typ 'sC signal .ing-.energization of the-decoding .transiormerpm for -controlling separate signal 'circui-ts, can be ;.mary-, winding, meanse effective-when said :relay is readily "changed to a" system as descri-bed ab'ove responding tolcoded energy of ithezfirst character -by -replacing' 'the decoding"relays and 1 theitsignal :for supplying energy .iromx the --decoding transwith:its control.circuits'by a:sing-lepunitary, self-: g former to said first control winding and means 'containedssignal of this sctype. :efiectivet-only when-said relayis responding to The above rather specific descriptionxofsevv coded.energyof-the second. characterifornsupplyv;eralsformsz whichnrthis invention can assume is mingener y fromitherdecodingtransformer to said argivencrsolely by wayrof nexamplegzand is snot'zin- ,rsecond eontrolwinding.

1-2tendedirrany-:mannerwhatsoever ina limitinggg OSCARLS. FIELD. 

